Systems and Methods for Utilizing Laser Cutting and Chemical Etching in Manufacturing Wireless Power Antennas

ABSTRACT

A PCB for wireless power transfer includes an antenna and the antenna includes a coil. A method for manufacturing the PCB includes providing a prefabricated PCB, the prefabricated PCB including a PCB design and a first area and providing a first sheet of a conductive metal for the first area. The method includes applying an etch resistant coating on a coil area within the first area and laser cutting the first sheet within the coil area, based on a laser cutting path for a first plurality of turns for a first layer of the coil, the first geometry configured wireless power transfer. The method further includes substantially exposing the first sheet to an etching solution, the etching solution substantially removing first portions of the conductive metal from the substrate to define, at least, first turn gaps between at least two of the first plurality of turns.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims priority to, U.S.application Ser. No. 17/135,029, filed on Dec. 28, 2020 and entitled“SYSTEMS AND METHODS FOR UTILIZING LASER CUTTING AND CHEMICAL ETCHING INMANUFACTURING WIRELESS POWER ANTENNAS,” which is incorporated byreference in its entirety.

TECHNICAL FIELD

The present disclosure generally relates to systems and methods formanufacturing wireless power transfer antennas, and, more particularly,to systems and methods utilizing laser cutting and chemical etching tomanufacture wireless power transfer antennas.

BACKGROUND

Wireless power transfer systems are used in a variety of applicationsfor the wireless transfer of electrical energy, electrical power,electromagnetic energy, electrical data signals, among other knownwirelessly transmittable signals. Such systems often use inductivewireless power transfer, which occurs when magnetic fields created by atransmitting element induce an electric field, and hence, an electriccurrent, in a receiving element. These transmission and receiverelements will often take the form of coiled wires and/or antennas.

Antennas utilized in wireless power transfer systems, generally,comprise one or more turns of a conductive wire and/or trace. Such turnscan be wire wound (e.g., physically winding a wire in a physical settingto create a form for the antenna coil) and, alternatively, such antennacoils can be printed, etched, and/or otherwise disposed on a circuitboard or printed circuit board (PCB). In some examples of PCB antennas,the PCB antennas may be disposed on a flexible printed circuit board(PCB), which may be utilized for fitting the antenna into tight spacesin modern electronics.

PCB circuit boards can be effectively manufactured utilizing an etchingprocess, where a sheet of conductive metal has a etch resistant coatingdisposed thereon in places that the manufacturer wants the antenna tolie. While PCB etching for wireless power transfer antennas can berelatively efficient and serves a need, in creating smaller sizedantennas, the electronic characteristics of the antenna are limited tothe precision of the etching process for achieving gap widths and turnwidths for the antenna coils.

SUMMARY

New systems and methods for manufacturing PCBs, which include wirelesspower antennas, are desired, wherein a combination of laser cutting theconductive metal and chemical etching of the conductive metal areutilized to produce a wireless power transfer antenna with enhancedelectrical characteristics, efficiency, and/or performance on aprefabricated PCB.

Transmission of one or more of electrical energy, electrical power,electromagnetic energy and electronic data signals from one of suchcoiled antennas to another, generally, operates at an operatingfrequency and/or an operating frequency range. The operating frequencymay be selected for a variety of reasons, such as, but not limited to,power transfer characteristics, power level characteristics,self-resonant frequency restraints, design requirements, adherence tostandards bodies' required characteristics, bill of materials (BOM)and/or form factor constraints, among other things. It is to be notedthat, “self-resonating frequency,” as known to those having skill in theart, generally refers to the resonant frequency of an inductor due tothe parasitic characteristics of the component.

Utilizing the systems and methods disclosed herein, the manufacturedantennas may allow for the ability to manufacture higher efficiencyand/or quality factor (Q) antennas for wireless power transfer, due toone or more of decrease in gap width, increases in turn width, orincreases in number of turns within a given area. Experimental resultshave shown that, when using the systems and methods disclosed herein,beneficial, narrow gap widths, which result in the benefits discussedabove, are achieved at various thicknesseses of copper for the metalsheets, such as a gap of about 50 microns when the copper is abouthalf-ounce copper, a gap of about 75 microns when the copper is aboutone-ounce copper, a gap of about 100 microns when the copper istwo-ounce copper, and a gap of about 125 microns when the copper isthree-ounce copper. Such narrow gap widths may allow for the performancebenefits and/or electrical characteristics, discussed above.

In some example experimental results wherein two ounce copper was usedfor the sheets of metal that were cut and etched to form the conductivelayer(s), utilizing the systems and methods disclosed herein, it wasfound that the processes could consistently achieve gap widths of about90-100 microns between turns of the conductive layer(s). Powercharacteristic test measurements were performed on the experimental testresults of the systems and methods disclosed herein and antennas wereproduced having at least about a 10 percent to 15 percent improvement inone or both of quality factor (Q) or equivalent series resistance (ESR)in the antenna, when compared to a comparable antenna, manufactured viaknown, conventional means for producing a PCB antenna. Further, it wasfound that improvements in efficiency, Q, and ESR were more pronouncedin antennas configured for operation at lower operating frequencies,such as those in a range of about 87 kHz to about 205 kHz.

Further, in addition to performance benefits achieved via the systemsand methods disclosed herein, the utilization of the combination oflaser cutting and chemical etching results in a decrease in time spentmanufacturing the antennas, in comparison to manufacturing legacyantennas. Additionally, the systems and methods disclosed herein canprovide for both faster and more cost-effective manufacturing, byutilizing the laser cutting and chemical etching combination, toaccelerate the speed of production of said antennas 21, 31.

In accordance with one aspect of the disclosure, a method formanufacturing a printed circuit board (PCB) for a wireless powertransfer system is disclosed. The PCB includes an antenna and theantenna includes a coil. The method includes providing a prefabricatedPCB, the prefabricated PCB including a PCB design and a first area. Themethod includes providing a first sheet of a conductive metal, the firstsheet including the first area. The method further includes applying anetch resistant coating on a coil area within the first area. The methodfurther includes laser cutting the first sheet within the coil area,based on a laser cutting path, the laser cutting path defining a firstgeometry for a first plurality of turns for a first layer of the coil,the first geometry configured for one or more of transmission ofwireless power signals, receipt of wireless power signals, andcombinations thereof. The method further includes substantially exposingthe first sheet to an etching solution, the etching solutionsubstantially removing first portions of the conductive metal from thesubstrate to define, at least, first turn gaps between at least two ofthe first plurality of turns.

In a refinement, the method further includes determining the coil areabased, at least, on an exterior geometry for the first coil layer.

In a refinement, the method further includes determining the lasercutting path based, at least, on one or more of the first geometry, anumber of turns for the plurality of turns, and any combinationsthereof.

In a refinement, the PCB design includes one or more of at least onetrace, at least one via, or combinations thereof.

In a further refinement, the method further includes providing apressure sensitive adhesive in between the first sheet and the substrateand affixing the sheet to the substrate includes affixing the firstsheet to the substrate via the pressure sensitive adhesive.

In another further refinement, the method further includes providing acoverlay substantially covering the first coil layer and the substrate.

In a refinement, the method further includes providing a second sheet ofa conductive metal, the second sheet defining a second area, applying anetch resistant coating on a second coil area within the second area,laser cutting the second sheet within the coil area, based on a secondlaser cutting path, the second laser cutting path defining a secondgeometry for a second plurality of turns for a second layer of the coil,the second geometry configured for one or more of transmission ofwireless power signals, receipt of wireless power signals, andcombinations thereof, and substantially exposing the second sheet to anetching solution, the etching solution substantially removing secondportions of the conductive metal, the second portions positioned todefine, at least, turn gaps between at least two of the second pluralityof turns.

In a refinement, the conductive metal is copper.

In a further refinement, the conductive metal is two-ounce copper andwherein the geometry defines at least one gap between two of theplurality of turns is less than about 140 microns.

In another further refinement, the conductive metal is three-ouncecopper and wherein the geometry defines at least one gap between two ofthe plurality of turns is less than about 150 microns.

In accordance with another aspect of the disclosure, a method formanufacturing a printed circuit board (PCB) for a wireless powertransfer system is disclosed. The PCB includes an antenna and theantenna includes a multi-layered coil having, at least, a first layerand a second layer. The method includes providing a prefabricated PCB,the prefabricated PCB including a PCB design, a first area, and a secondarea. The method further includes providing a first sheet of aconductive metal, the first sheet including the first area and providinga second sheet of a conductive metal, the second sheet defining a secondarea. The method includes applying an etch resistant coating on a firstcoil area within the first area and applying an etch resistant coatingon a second coil area within the second area. The method furtherincludes laser cutting the first sheet within the first coil area, basedon a first laser cutting path, the first laser cutting path defining afirst geometry for a first plurality of turns for a first layer of thecoil, the first geometry configured for one or more of transmission ofwireless power signals, receipt of wireless power signals, andcombinations thereof. The method further includes laser cutting thesecond sheet within the second coil area, based on a second lasercutting path, the second laser cutting path defining a second geometryfor a second plurality of turns for a second layer of the coil, thesecond geometry configured for one or more of transmission of wirelesspower signals, receipt of wireless power signals, and combinationsthereof. The method further includes substantially exposing the firstsheet to an etching solution, the etching solution substantiallyremoving first portions of the conductive metal from the substrate todefine, at least, first turn gaps between at least two of the firstplurality of turns. The method further includes substantially exposingthe second sheet to an etching solution, the etching solutionsubstantially removing second portions of the conductive metal from thesubstrate to define, at least, second turn gaps between at least two ofthe second plurality of turns.

In a refinement, the method further includes welding the first layer ofthe coil to the second layer of the coil.

In a further refinement, welding the first layer of the coil to thesecond layer of the coil includes spot welding the first layer of thecoil to the second layer of the coil at a mutual connection point.

In an even further refinement, the via is configured to connect thefirst layer of the coil to the second layer of the coil in a parallelelectrical connection.

In a refinement, the method further includes affixing the first sheet toa top face of a substrate and affixing the second sheet to a bottom faceof the substrate.

In a further refinement, the method further includes providing a firstpressure sensitive adhesive in between the first layer and the top faceof the substrate and providing a second pressure sensitive adhesive inbetween the second layer and the bottom face of the substrate, whereinaffixing the first layer to the substrate includes affixing the firstlayer to the top face of the substrate via the first pressure sensitiveadhesive, and wherein affixing the second layer to the substrateincludes affixing the second layer to the bottom face of the substratevia the second pressure sensitive adhesive.

In an even further refinement, providing the first pressure sensitiveadhesive includes providing a first cutout in the first pressuresensitive adhesive and providing the second pressure sensitive adhesiveincludes providing a second cutout in the first pressure sensitiveadhesive, and the first and second cutouts are configured at a locationfor a spot weld between the first sheet and the second sheet.

In an even further refinement, the method further includes spot weldingthe first sheet and the second sheet at a location proximate to thefirst and second cutouts.

In yet another aspect of the disclosure, a PCB for a wireless powertransfer system is disclosed. The PCB includes a coil, the coilincluding a first layer, wherein the first layer defines a firstplurality of turns, the first plurality of turns formed by providing aprefabricated PCB, the prefabricated PCB including a PCB design and afirst area, providing a first sheet of a conductive metal, the firstsheet including the first area, applying an etch resistant coating on acoil area within the first area, laser cutting the first sheet withinthe coil area, based on a laser cutting path, the laser cutting pathdefining a first geometry for the plurality of turns for the first layerof the coil, the first geometry configured for one or more oftransmission of wireless power signals, receipt of wireless powersignals, and combinations thereof, and substantially exposing the firstsheet to an etching solution, the etching solution substantiallyremoving first portions of the conductive metal from the substrate todefine, at least, first turn gaps between at least two of the firstplurality of turns.

In a refinement, the coil further includes a second layer, the secondlayer defining a second plurality of turns, the second plurality ofturns formed by providing a second sheet of a conductive metal, thesecond sheet defining a second area, applying an etch resistant coatingon a second coil area within the second area, laser cutting the secondsheet within the second coil area, based on a laser cutting path, thelaser cutting path defining a second geometry for the second pluralityof turns for the second layer of the coil, the second geometryconfigured for one or more of transmission of wireless power signals,receipt of wireless power signals, and combinations thereof,substantially exposing the second sheet to an etching solution, theetching solution substantially removing second portions of theconductive metal from the substrate to define, at least, second turngaps between at least two of the second plurality of turns. wherein thefirst layer is affixed to a top face of the substrate, and wherein thesecond layer is affixed to a bottom face of the substrate.

These and other aspects and features of the present disclosure will bebetter understood when read in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an embodiment of a system for wirelesslytransferring one or more of electrical energy, electrical power,electromagnetic energy electronic data, and combinations thereof, inaccordance with the present disclosure.

FIG. 2 is a block diagram illustrating components of a wirelesstransmission system of the system of FIG. 1 and a wireless receiversystem of the system of FIG. 1 , in accordance with FIG. 1 and thepresent disclosure.

FIG. 3 is a block diagram illustrating components of a transmissioncontrol system of the wireless transmission system of FIG. 2 , inaccordance with FIG. 1 , FIG. 2 , and the present disclosure.

FIG. 4 is a block diagram illustrating components of a sensing system ofthe transmission control system of FIG. 3 , in accordance with FIGS. 1-3and the present disclosure.

FIG. 5A is a top view of an exemplary wireless power antenna, for usewith, for example, the systems of FIGS. 1-4 , and manufactured via thesystems and methods disclosed herein, in accordance with FIGS. 1-4 andthe present disclosure.

FIG. 5B is a bottom view of the exemplary wireless power antenna of FIG.5A, in accordance with FIGS. 1-5A and the present disclosure.

FIG. 5C is an exploded view of components of the exemplary wirelesspower antenna of FIGS. 5A and 5B, in accordance with FIGS. 1-5B and thepresent disclosure.

FIG. 6 is a flowchart for an exemplary method for manufacturing thewireless power antenna of FIGS. 5A-C, in accordance with FIGS. 1-5C andthe present disclosure.

FIG. 7A is a top view of another exemplary wireless power antenna, foruse with, for example, the systems of FIGS. 1-4 , and manufactured viathe systems and methods disclosed herein, in accordance with FIGS. 1-6and the present disclosure.

FIG. 7B is a bottom view of the exemplary wireless power antenna of FIG.7A, in accordance with FIGS. 1-7A and the present disclosure.

FIG. 7C is an exploded view of components of the exemplary wirelesspower antenna of FIGS. 7A and 7B, in accordance with FIGS. 1-7B and thepresent disclosure.

FIG. 8 is a flowchart for an exemplary method for manufacturing thewireless power antenna of FIGS. 7A-C, in accordance with FIGS. 1-7C andthe present disclosure.

FIG. 9 is a zoomed in image of an exemplary layer of conductive metal ofan antenna, subsequent to a laser cutting step of the systems andmethods disclosed herein, in accordance with FIGS. 1-8 and the presentdisclosure.

FIG. 10 is a zoomed in image of a layer of conductive metal, etchedutilizing legacy methods for etching traces and/or gaps for an antenna.

FIG. 11 is a zoomed in image of a cross-section of two layers ofconductive metal, etched utilizing legacy methods for etching tracesand/or gaps for an antenna.

While the following detailed description will be given with respect tocertain illustrative embodiments, it should be understood that thedrawings are not necessarily to scale and the disclosed embodiments aresometimes illustrated diagrammatically and in partial views. Inaddition, in certain instances, details which are not necessary for anunderstanding of the disclosed subject matter or which render otherdetails too difficult to perceive may have been omitted. It shouldtherefore be understood that this disclosure is not limited to theparticular embodiments disclosed and illustrated herein, but rather to afair reading of the entire disclosure and claims, as well as anyequivalents thereto. Additional, different, or fewer components andmethods may be included in the systems and methods.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth byway of examples in order to provide a thorough understanding of therelevant teachings. However, it should be apparent to those skilled inthe art that the present teachings may be practiced without suchdetails. In other instances, well known methods, procedures, components,and/or circuitry have been described at a relatively high-level, withoutdetail, in order to avoid unnecessarily obscuring aspects of the presentteachings.

Referring now to the drawings and with specific reference to FIG. 1 , awireless power transfer system 10 is illustrated. The wireless powertransfer system 10 provides for the wireless transmission of electricalsignals, such as, but not limited to, electrical energy, electricalpower, electrical power signals, electromagnetic energy, andelectronically transmittable data (“electronic data”). Specifically, thewireless power transfer 10 provides for the wireless transmission ofelectrical signals via near field magnetic coupling. As shown in theembodiment of FIG. 1 , the wireless power transfer 10 includes awireless transmission system 20 and a wireless receiver system 30. Thewireless receiver system is configured to receive electrical energy,electrical power, electromagnetic energy, electrical power signals,and/or electronic data from, at least, the wireless transmission system20.

As illustrated, the wireless transmission system 20 and wirelessreceiver system 30 may be configured to transmit electrical energy,electrical power, electromagnetic energy, electrical power signals,and/or electronically transmittable data across, at least, a separationdistance or gap 17. A separation distance or gap, such as the gap 17, inthe context of a wireless power transfer systems, such as the system 10,does not include a physical connection, such as a wired connection.There may be intermediary objects located in a separation distance orgap, such as the gap 17, such as, but not limited to, air, a countertop, a casing for an electronic device, a plastic filament, aninsulator, a mechanical wall, among other things; however, there is nophysical, electrical connection at such a separation distance or gap.

Thus, the combination of the wireless transmission system 20 and thewireless receiver system 30 create an electrical connection without theneed for a physical connection. “Electrical connection,” as definedherein, refers to any facilitation of a transfer of an electricalcurrent, voltage, and/or power from a first location, device, component,and/or source to a second location, device, component, and/ordestination. An “electrical connection” may be a physical connection,such as, but not limited to, a wire, a trace, a via, among otherphysical electrical connections, connecting a first location, device,component, and/or source to a second location, device, component, and/ordestination. Additionally or alternatively, an “electrical connection”may be a wireless electrical connection, such as, but not limited to,magnetic, electromagnetic, resonant, and/or inductive field, among otherwireless electrical connections, connecting a first location, device,component, and/or source to a second location, device, component, and/ordestination.

Alternatively, the gap 17 may be referenced as a “Z-Distance,” because,if one considers an antenna 21, 31 to be disposed substantially along acommon X-Y plane, then the distance separating the antennas 21, 31 isthe gap in a “Z” or “depth” direction. However, flexible and/ornon-planar coils are certainly contemplated by embodiments of thepresent disclosure and, thus, it is contemplated that the gap 17 may notbe uniform, across an envelope of connection distances between theantennas 21 ,31. It is contemplated that various tunings,configurations, and/or other parameters may alter the possible maximumdistance of the gap 17, such that electrical transmission from thewireless transmission system 20 to the wireless receiver system 30remains possible.

The wireless power system 10 operates when the wireless transmissionsystem 20 and the wireless receiver system 30 are coupled. As definedherein, the terms “couples,” “coupled,” and “coupling” generally refersto magnetic field coupling, which occurs when the energy of atransmitter and/or any components thereof and the energy of a receiverand/or any components thereof are coupled to each other through amagnetic field. Coupling of the wireless transmission system 20 and thewireless receiver system 30, in the system 10, may be represented by aresonant coupling coefficient of the system 10 and, for the purposes ofwireless power transfer, the coupling coefficient for the system 10 maybe in the range of about 0.01 and 0.9.

As illustrated, the wireless transmission system 20 may be associatedwith a host device 11, which may receive power from an input powersource 12. The host device 11 may be any electrically operated device,circuit board, electronic assembly, dedicated charging device, or anyother contemplated electronic device. Example host devices 11, withwhich the wireless transmission system 20 may be associated therewith,include, but are not limited to including, a device that includes anintegrated circuit, cases for wearable electronic devices, receptaclesfor electronic devices, a portable computing device, clothing configuredwith electronics, storage medium for electronic devices, chargingapparatus for one or multiple electronic devices, dedicated electricalcharging devices, activity or sport related equipment, goods, and/ordata collection devices, among other contemplated electronic devices.

As illustrated, one or both of the wireless transmission system 20 andthe host device 11 are operatively associated with an input power source12. The input power source 12 may be or may include one or moreelectrical storage devices, such as an electrochemical cell, a batterypack, and/or a capacitor, among other storage devices. Additionally oralternatively, the input power source 12 may be any electrical inputsource (e.g., any alternating current (AC) or direct current (DC)delivery port) and may include connection apparatus from said electricalinput source to the wireless transmission system 20 (e.g., transformers,regulators, conductive conduits, traces, wires, or equipment, goods,computer, camera, mobile phone, and/or other electrical deviceconnection ports and/or adaptors, such as but not limited to USB or mp3ports and/or adaptors, among other contemplated electrical components).

Electrical energy received by the wireless transmission system 20 isthen used for at least two purposes: providing electrical power tointernal components of the wireless transmission system 20 and providingelectrical power to the transmitter antenna 21. The transmitter antenna21 is configured to wirelessly transmit the electrical signalsconditioned and modified for wireless transmission by the wirelesstransmission system 20 via near-field magnetic coupling (NFMC).Near-field magnetic coupling enables the transfer of electrical energy,electrical power, electromagnetic energy, and/or electronicallytransmissible data wirelessly through magnetic induction between thetransmitter antenna 21 and a receiving antenna 31 of, or associatedwith, the wireless receiver system 30. Near-field magnetic coupling mayenable “inductive coupling,” which, as defined herein, is a wirelesspower transmission technique that utilizes an alternatingelectromagnetic field to transfer electrical energy between twoantennas. Such inductive coupling is the near field wirelesstransmission of electrical energy between two magnetically coupled coilsthat are tuned to resonate at a similar frequency. Further, suchnear-field magnetic coupling may provide connection via “mutualinductance,” which, as defined herein is the production of anelectromotive force in a circuit by a change in current in a secondcircuit magnetically coupled to the first.

In one or more embodiments, the inductor coils of either the transmitterantenna 21 or the receiver antenna 31 are strategically positioned tofacilitate reception and/or transmission of wirelessly transferredelectrical energy, power, electromagnetic energy and/or data throughnear field magnetic induction. Antenna operating frequencies maycomprise all operating frequency ranges, examples of which may include,but are not limited to, about 87 kHz to about 205 kHz (Qi interfacestandard), 100 kHz to about 350 kHz (PMA interface standard), 6.78 MHz(Rezence interface standard and/or any other proprietary interfacestandard operating at a frequency of 6.78 MHz), 13.56 MHz (Near FieldCommunications (NFC) standard, defined by ISO/IEC standard 18092), 27MHz and/or, alternatively, at an operating frequency of anotherproprietary operating mode. The operating frequencies of the antennas21, 31 may be operating frequencies designated by the InternationalTelecommunications Union (ITU) in the Industrial, Scientific, andMedical (ISM) frequency bands, which include, but are not limited toincluding, 6.78 MHz, 13.56 MHz, and 27 MHz, which are designated for usein wireless power transfer.

In addition, the transmitting antenna and/or the receiving antenna ofthe present disclosure may be designed to transmit or receive,respectively, over a wide range of operating frequencies on the order ofabout 1 kHz to about 1 GHz or greater, in addition to the Qi, PMA,Rezence, and NFC interface standards. The transmitting antenna and thereceiving antenna of the present disclosure may be configured totransmit and/or receive electrical power having a magnitude that rangesfrom about 10 mW to about 500 W. In one or more embodiments the inductorcoil of the transmitting antenna 21 is configured to resonate at atransmitting antenna resonant frequency or within a transmitting antennaresonant frequency band.

As known to those skilled in the art, a “resonant frequency” or“resonant frequency band” refers a frequency or frequencies whereinamplitude response of the antenna is at a relative maximum, or,additionally or alternatively, the frequency or frequency band where thecapacitive reactance has a magnitude substantially similar to themagnitude of the inductive reactance. In one or more embodiments thetransmitting antenna resonant frequency is at least 1 kHz. In one ormore embodiments the transmitting antenna resonant frequency bandextends from about 1 kHz to about 100 MHz. In one or more embodimentsthe inductor coil of the receiving antenna 31 is configured to resonateat a receiving antenna resonant frequency or within a receiving antennaresonant frequency band. In one or more embodiments the receivingantenna resonant frequency is at least 1 kHz. In one or more embodimentsthe receiving antenna resonant frequency band extends from about 1 kHzto about 100 MHz.

The wireless receiver system 30 may be associated with at least oneelectronic device 14, wherein the electronic device 14 may be any devicethat requires electrical power for any function and/or for power storage(e.g., via a battery and/or capacitor). Additionally or alternatively,the electronic device 14 may be any device capable of receipt ofelectronically transmissible data. For example, the device may be, butis not limited to being, a handheld computing device, a mobile device, aportable appliance, an integrated circuit, an identifiable tag, akitchen utility device, an electronic tool, an electric vehicle, a gameconsole, a robotic device, a wearable electronic device (e.g., anelectronic watch, electronically modified glasses, altered-reality (AR)glasses, virtual reality (VR) glasses, among other things), a portablescanning device, a portable identifying device, a sporting good, anembedded sensor, an Internet of Things (IoT) sensor, IoT enabledclothing, IoT enabled recreational equipment, industrial equipment,medical equipment, a medical device a tablet computing device, aportable control device, a remote controller for an electronic device, agaming controller, among other things.

For the purposes of illustrating the features and characteristics of thedisclosed embodiments, arrow-ended lines are utilized to illustratetransferrable and/or communicative signals and various patterns are usedto illustrate electrical signals that are intended for powertransmission and electrical signals that are intended for thetransmission of data and/or control instructions. Solid lines indicatesignal transmission of electrical energy over a physical and/or wirelesselectrical connection, in the form of power signals that are,ultimately, utilized in wireless power transmission from the wirelesstransmission system 20 to the wireless receiver system 30. Further,dotted lines are utilized to illustrate electronically transmittabledata signals, which ultimately may be wirelessly transmitted from thewireless transmission system 20 to the wireless receiver system 30.

While the systems and methods herein illustrate the transmission ofwirelessly transmitted energy, wirelessly transmitted power, wirelesslytransmitted electromagnetic energy, and electronically transmittabledata, it is certainly contemplated that the systems, methods, andapparatus disclosed herein may be utilized in the transmission of onlyone signal, various combinations of two signals, or more than twosignals and, further, it is contemplated that the systems, method, andapparatus disclosed herein may be utilized for wireless transmission ofother electrical signals in addition to or uniquely in combination withone or more of the above mentioned signals. In some examples, the signalpaths of solid or dotted lines may represent a functional signal path,whereas, in practical application, the actual signal is routed throughadditional components en route to its indicated destination. Forexample, it may be indicated that a data signal routes from acommunications apparatus to another communications apparatus; however,in practical application, the data signal may be routed through anamplifier, then through a transmission antenna, to a receiver antenna,where, on the receiver end, the data signal is decoded by a respectivecommunications device of the receiver.

Turning now to FIG. 2 , the wireless power transfer 10 is illustrated asa block diagram including example sub-systems of both the wirelesstransmission system 20 and the wireless receiver system 30. The wirelesstransmission system 20 may include, at least, a power conditioningsystem 40, a transmission control system 26, a transmission tuningsystem 24, and the transmission antenna 21. A first portion of theelectrical energy input from the input power source 12 is configured toelectrically power components of the wireless transmission system 20such as, but not limited to, the transmission control system 26. Asecond portion of the electrical energy input from the input powersource 12 is conditioned and/or modified for wireless powertransmission, to the wireless receiver system 30, via the transmissionantenna 21. Accordingly, the second portion of the input energy ismodified and/or conditioned by the power conditioning system 40. Whilenot illustrated, it is certainly contemplated that one or both of thefirst and second portions of the input electrical energy may bemodified, conditioned, altered, and/or otherwise changed prior toreceipt by the power conditioning system 40 and/or transmission controlsystem 26, by further contemplated subsystems (e.g., a voltageregulator, a current regulator, switching systems, fault systems, safetyregulators, among other things).

Referring now to FIG. 3 , with continued reference to FIGS. 1 and 2 ,subcomponents and/or systems of the transmission control system 26 areillustrated. The transmission control system 26 may include a sensingsystem 50, a transmission controller 28, a communications system 29, adriver 48, and a memory 27.

The transmission controller 28 may be any electronic controller orcomputing system that includes, at least, a processor which performsoperations, executes control algorithms, stores data, retrieves data,gathers data, controls and/or provides communication with othercomponents and/or subsystems associated with the wireless transmissionsystem 20, and/or performs any other computing or controlling taskdesired. The transmission controller 28 may be a single controller ormay include more than one controller disposed to control variousfunctions and/or features of the wireless transmission system 20.Functionality of the transmission controller 28 may be implemented inhardware and/or software and may rely on one or more data maps relatingto the operation of the wireless transmission system 20. To that end,the transmission controller 28 may be operatively associated with thememory 27. The memory may include one or more of internal memory,external memory, and/or remote memory (e.g., a database and/or serveroperatively connected to the transmission controller 28 via a network,such as, but not limited to, the Internet). The internal memory and/orexternal memory may include, but are not limited to including, one ormore of a read only memory (ROM), including programmable read-onlymemory (PROM), erasable programmable read-only memory (EPROM orsometimes but rarely labelled EROM), electrically erasable programmableread-only memory (EEPROM), random access memory (RAM), including dynamicRAM (DRAM), static RAM (SRAM), synchronous dynamic RAM (SDRAM), singledata rate synchronous dynamic RAM (SDR SDRAM), double data ratesynchronous dynamic RAM (DDR SDRAM, DDR2, DDR3, DDR4), and graphicsdouble data rate synchronous dynamic RAM (GDDR SDRAM, GDDR2, GDDR3,GDDR4, GDDR5, a flash memory, a portable memory, and the like. Suchmemory media are examples of nontransitory machine readable and/orcomputer readable memory media.

While particular elements of the transmission control system 26 areillustrated as independent components and/or circuits (e.g., the driver48, the memory 27, the communications system 29, the sensing system 50,among other contemplated elements) of the transmission control system26, such components may be integrated with the transmission controller28. In some examples, the transmission controller 28 may be anintegrated circuit configured to include functional elements of one orboth of the transmission controller 28 and the wireless transmissionsystem 20, generally.

As illustrated, the transmission controller 28 is in operativeassociation, for the purposes of data transmission, receipt, and/orcommunication, with, at least, the memory 27, the communications system29, the power conditioning system 40, the driver 48, and the sensingsystem 50. The driver 48 may be implemented to control, at least inpart, the operation of the power conditioning system 40. In someexamples, the driver 48 may receive instructions from the transmissioncontroller 28 to generate and/or output a generated pulse widthmodulation (PWM) signal to the power conditioning system 40. In somesuch examples, the PWM signal may be configured to drive the powerconditioning system 40 to output electrical power as an alternatingcurrent signal, having an operating frequency defined by the PWM signal.

The sensing system may include one or more sensors, wherein each sensormay be operatively associated with one or more components of thewireless transmission system 20 and configured to provide informationand/or data. The term “sensor” is used in its broadest interpretation todefine one or more components operatively associated with the wirelesstransmission system 20 that operate to sense functions, conditions,electrical characteristics, operations, and/or operating characteristicsof one or more of the wireless transmission system 20, the wirelessreceiving system 30, the input power source 12, the host device 11, thetransmission antenna 21, the receiver antenna 31, along with any othercomponents and/or subcomponents thereof.

At the power conditioning system 40, electrical power is received,generally, as a direct current (DC) power source, via the input powersource 12 itself or an intervening power converter, converting an ACsource to a DC source (not shown). The power conditioning system 40 mayprovide a first electrical power signal to electrically power anycomponents of the wireless transmission system 20 and a second portionconditioned and modified for wireless transmission to the wirelessreceiver system 30. As illustrated in FIG. 3 , such a first portion istransmitted to, at least, the sensing system 50, the transmissioncontroller 28, and the communications system 29; however, the firstportion is not limited to transmission to just these components and canbe transmitted to any electrical components of the wireless transmissionsystem 20.

The second portion of the electrical power may be provided to anamplifier of the power conditioning system 40, which is configured tocondition the electrical power for wireless transmission by the antenna21. The amplifier may function as an invertor, which receives an inputDC power signal and generates an alternating current (AC) as output,based, at least in part, on PWM input from the transmission controlsystem 26. Such an amplifier may be or include, for example, a powerstage inverter, such as a dual field effect transistor power stageinvertor. The power conditioning system 40 and, in turn, the wirelesstransmission system 20 enables wireless transmission of electricalsignals having much greater amplitudes than if transmitted without suchpower conditioning. For example, the power conditioning system 40 mayenable the wireless transmission system 20 to transmit electrical energyas an electrical power signal having electrical power from about 10 mWto about 500 W.

Returning now to FIG. 2 , the conditioned signal(s) from the powerconditioning system 40 is then received by the transmission tuningsystem 24, prior to transmission by the antenna. The transmission tuningsystem 24 may include tuning and/or impedance matching, filters (e.g. alow pass filter, a high pass filter, a “pi” or “Π” filter, a “T” filter,an “L” filter, a “LL” filter, an L-C trap filter, among other filters),network matching, sensing, and/or conditioning elements configured tooptimize wireless transfer of signals from the wireless transmissionsystem 20 to the wireless receiver system 30. Further, the transmissiontuning system 24 may include an impedance matching circuit, which isdesigned to match impedance with a corresponding wireless receiversystem 30 for given power, current, and/or voltage requirements forwireless transmission of one or more of electrical energy, electricalpower, electromagnetic energy, and electronic data.

Turning now to FIG. 4 and with continued reference to, at least, FIGS. 1and 2 , the wireless receiver system 30 is illustrated in furtherdetail. The wireless receiver system 30 is configured to receive, atleast, electrical energy, electrical power, electromagnetic energy,and/or electrically transmittable data via near field magnetic couplingfrom the wireless transmission system 20, via the transmission antenna21. As illustrated in FIG. 4 , the wireless receiver system 30 includes,at least, the receiver antenna 31, a receiver tuning system 34, a powerconditioning system 32, and a receiver control system 36. The receivertuning system 34 may be configured to substantially match the electricalimpedance of the wireless transmission system 20. In some examples, thereceiver tuning system 34 may be configured to dynamically adjust andsubstantially match the electrical impedance of the receiver antenna 31to a characteristic impedance of the power generator or the load at adriving frequency of the transmission antenna 20.

As illustrated, the power conditioning system 32 includes a rectifier 33and a voltage regulator 35. In some examples, the rectifier 33 is inelectrical connection with the receiver tuning system 34. The rectifier33 is configured to modify the received electrical energy from analternating current electrical energy signal to a direct currentelectrical energy signal. In some examples, the rectifier 33 iscomprised of at least one diode. Some non-limiting exampleconfigurations for the rectifier 33 include, but are not limited toincluding, a full wave rectifier, including a center tapped full waverectifier and a full wave rectifier with filter, a half wave rectifier,including a half wave rectifier with filter, a bridge rectifier,including a bridge rectifier with filter, a split supply rectifier, asingle phase rectifier, a three phase rectifier, a controlled rectifier,an uncontrolled rectifier, and a half controlled rectifier. Aselectronic devices may be sensitive to voltage, additional protection ofthe electronic device may be provided by clipper circuits or devices.The rectifier 33 may further include a clipper circuit or a clipperdevice. A clipper is herein defined as a circuit or device that removeseither the positive half (top half), the negative half (bottom half), orboth the positive and the negative halves of an input AC signal. Inother words, a clipper is a circuit or device that limits the positiveamplitude, the negative amplitude, or both the positive and the negativeamplitudes of the input AC signal.

Some non-limiting examples of a voltage regulator 35 include, but arenot limited to, including a series linear voltage regulator, a shuntlinear voltage regulator, a block up switching voltage regulator, ablock down switching voltage regulator, an inverter voltage regulator, aZener controlled transistor series voltage regulator, and an emitterfollower voltage regulator. The voltage regulator 35 may further includea voltage multiplier. A voltage multiplier is herein defined as anelectronic circuit or device that delivers an output voltage having anamplitude (peak value) that is two, three, or more times greater thanthe amplitude (peak value) of the input voltage. The voltage regulator35 is in electrical connection with the rectifier 33 and configured toadjust the amplitude of the electrical voltage of the wirelesslyreceived electrical energy signal, after conversion to AC by therectifier 33. In some examples, the voltage regulator 35 may be a lowdropout linear voltage regulator; however, other voltage regulationcircuits and/or systems are contemplated. As illustrated, the directcurrent electrical energy signal output by the voltage regulator 35 isreceived at the load 16 of the electronic device 14. In some examples, aportion of the direct current electrical power signal may be utilized topower the receiver control system 36 and any components thereof;however, it is certainly possible that the receiver control system 36,and any components thereof, may be powered and/or receive signals fromthe load 16 and/or other components of the electronic device 14.

The receiver control system 36 may include, but is not limited to,including a receiver controller 38, a communications system 39, and amemory 37. The receiver controller 38 may be any electronic controlleror computing system that includes, at least, a processor which performsoperations, executes control algorithms, stores data, retrieves data,gathers data, controls and/or provides communication with othercomponents and/or subsystems associated with the wireless receiversystem 30. The receiver controller 38 may be a single controller or mayinclude more than one controller disposed to control various functionsand/or features of the wireless receiver system 30. Functionality of thetransmission controller 38 may be implemented in hardware and/orsoftware and may rely on one or more data maps relating to the operationof the wireless receiver system 30. To that end, the receiver controller38 may be operatively associated with the memory 37. The memory mayinclude one or both of internal memory, external memory, and/or remotememory (e.g., a database and/or server operatively connected to thereceiver controller 28 via a network, such as, but not limited to, theInternet). The internal memory and/or external memory may include, butare not limited to including, one or more of a read only memory (ROM),including programmable read-only memory (PROM), erasable programmableread-only memory (EPROM or sometimes but rarely labelled EROM),electrically erasable programmable read-only memory (EEPROM), randomaccess memory (RAM), including dynamic RAM (DRAM), static RAM (SRAM),synchronous dynamic RAM (SDRAM), single data rate synchronous dynamicRAM (SDR SDRAM), double data rate synchronous dynamic RAM (DDR SDRAM,DDR2, DDR3, DDR4), and graphics double data rate synchronous dynamic RAM(GDDR SDRAM, GDDR2, GDDR3, GDDR4, GDDR5, a flash memory, a portablememory, and the like. Such memory media are examples of nontransitorycomputer readable memory media.

Further, while particular elements of the receiver control system 36 areillustrated as independent components and/or circuits (e.g., the memory37, the communications system 39, among other contemplated elements) ofthe receiver control system 36, such components may be integrated withthe receiver controller 38. In some examples, the receiver controller 38may be and/or include one or more integrated circuits configured toinclude functional elements of one or both of the receiver controller 38and the wireless receiver system 30, generally. “Integrated circuits,”as defined herein, generally refers to a circuit in which all or some ofthe circuit elements are inseparably associated and electricallyinterconnected so that it is considered to be indivisible for thepurposes of construction and commerce. Such integrated circuits mayinclude, but are not limited to including, thin-film transistors,thick-film technologies, and/or hybrid integrated circuits.

Turning now to FIG. 5A, an exemplary embodiment of one or more of thetransmission antenna 21 or the receiver antenna 31, which may be usedwith any of the systems, methods, and/or apparatus disclosed herein, isillustrated. In the exemplary embodiment, the antenna 21, 31, is a flatcoil disposed on a substrate 50 of a prefabricated PCB 70. Theprefabricated PCB 70A may be any prefabricated PCB that has been cut,etched, chemically etched, plated, and/or otherwise formed, prior to theformation of the antenna 21A in accordance with the systems and methodsdisclosed herein. The prefabricated PCB 70 may include a PCB design 72,which includes any features for an electronic circuit board, such as,but not limited to, a plurality of traces 74 and a plurality of vias 76.The traces 74 may be utilized to electrically connect components forplacement on the prefabricated PCB 70, which may include one or morecomponents of the wireless transmission system 20, the wireless receiversystem 30, and/or any components thereof. The vias 76 may be utilized asconnection points for said components, for connection to theprefabricated PCB 70, the antenna 21, 31, and/or connection to any ofthe aforementioned components. A coil area 60 may be designed onto theprefabricated PCB 70, such that the systems and methods disclosed hereinmay be utilized to laser cut and etch the antenna 21, 31 in the coilarea 60.

In the exemplary embodiment shown, the antenna comprises at least onelayer of a electrical conductor and at least one electrically insulatinglayer. In some examples, the antenna 21, 31 may be a multi-layermulti-turn (MLMT) antenna, comprising two or more electrically connectedlayers of conductors or coils. Non-limiting examples of MLMT antennascan be found in, at least, U.S. Pat. Nos. 9,941,743, 9,960,628,9,941,743 all to Peralta et al., U.S. Pat. Nos. 9,948,129, 10,063,100 toSingh et al., U.S. Pat. No. 9,941,590 to Luzinski, U.S. Pat. No.9,960,629 to Rajagopalan et al. and U.S. Patent App. Nos. 2017/0040107,2017/0040105, 2017/0040688 to Peralta et al., all of which are assignedto the assignee of the present application and incorporated fully hereinby reference.

In addition, the antenna 21, 31, 121 may be constructed having amulti-layer-multi-turn (MLMT) construction in which at least oneinsulator is positioned between a plurality of conductors. Non-limitingexamples of antennas having an MLMT construction that may beincorporated within the wireless transmission system(s) 20 and/or thewireless receiver system(s) 30 may be found in U.S. Pat. Nos. 8,610,530,8,653,927, 8,680,960, 8,692,641, 8,692,642, 8,698,590, 8,698,591,8,707,546, 8,710,948, 8,803,649, 8,823,481, 8,823,482, 8,855,786,8,898,885, 9,208,942, 9,232,893, 9,300,046, all to Singh et al.,assigned to the assignee of the present application are incorporatedfully herein.

As illustrated, the antenna 21, 31 includes, at least, a firstconductive layer 40 disposed on a substrate 50, the first conductivelayer 40 including a plurality of coil turns 42. Each of the pluralityof coil turns are separated by a turn gap 44, which is best illustratedin the exemplary zoomed-in portion A of the antenna 21, 31. Portion Aillustrates exemplary turns 42 of the antenna 21, 31, with turn gaps 44in between. The antenna 21, 31 further includes, at least, a firstconnection terminal 45 and a second connection terminal 46. The firstand second connection terminals 45, 46 may be utilized for one or moreof electrically connecting the antenna 21, 31 to other components of oneor more of the wireless transmission system 20, the wireless receiversystem 30, or the system 10. In some examples, the connection terminals45, 46 may be connected to other components of the prefabricated PCB 70,via, for example, one or more traces 74 and/or vias 76. Additionally oralternatively, the connection terminals 45, 46 may be utilized forconnecting the first conductive layer 40 to one or more additionalconductive layers of the antenna 21, 31, which will be discussed in moredetail, below, with reference to other embodiments for the antenna 21,31.

Further, as illustrated in FIG. 5B, which shows an exemplary rear sideof the antenna 21, 31, wherein the antenna 21, 31 includes first andsecond rear connectors 27, 28 which, similarly to the first and secondconnection terminals 45, 46, may be utilized for one or more ofelectrically connecting the antenna 21, 31 to other components of one ormore of the wireless transmission system 20, the wireless receiversystem 30, or the system 10. Additionally or alternatively, the rearconnection terminals 47, 48 may be utilized for connecting the firstconductive layer 40 and/or one or more other conductive layers toanother conductive layer of the antenna 21, 31, which will be discussedin more detail, below, with reference to other embodiments for theantenna 21, 31.

FIG. 5C illustrates an exploded view of an assembly for an embodiment ofthe antenna 21, 31. As illustrated, the antenna 21, 31 includes thesubstrate 50 with the at least one conductive layer 40 affixed thereto.In designing an antenna, it is understood that suitability of thesubstrate relative to the application is an important, as the substrateproperties such as, but not limited to, the dielectric constant, theloss tangent, and/or the relative permittivity of the substrate; suchsubstrate properties can have significant effect on the antennacharacteristics.

The substrate 50 may be comprised of, for example, a polymer layer. Thesubstrate may further be selected from the group consisting of a paperbase class, a glass fiber cloth base class, a composite epoxy material(CEM), a lamination multilayer base class, a special material baseclass, a flame-proof type, a non-flameproof type, a copper clad laminate(CCL) with ordinary performance, a CCL with low dielectric constant, aCCL with high heat resistance, a CCL with low coefficient of thermalexpansion, and combinations thereof. A paper base class may furthercomprise a phenolic resin or a phenol formaldehyde resin (PF), such asANSI-LI-1 XPC (BS 4584 PF-CP-Cu-4), ANSI-LI-1 FR1 (BS 4584 PF-CP-Cu-6),ANSI LI-1 FR2 (BS 4584 PF-CP-Cu-8), an epoxy resin (FE-3), a polyesterresin, aramid papers or combinations thereof. A glass fiber cloth baseclass may further comprise an epoxy resin such as ANSI-LI-1 FR4 (BS 4584EP-GC-Cu-2), FR5 (similar to FR4 but in a high temperature epoxy resin)and combinations thereof. A special material base class may furthercomprise a ceramic, such as alumina, metal core base, glass fiber cloth,polyamide, non-woven fabrics, bismaleimide trazine (BT) epoxy or resin,polyimide (PI), polyphenylene oxide (PPO), maleic anhydrideimide-styrene (MS) resin, polycyclic ester resin, polyolefin resin,multi-functional epoxy, tetra-functional epoxy, cyanate ester, teflon,fluorine-based resin or combinations thereof. A flameproof type resinmay further comprise UL94 materials for example, UL94-VO , UL94-V1, orcombinations thereof. A non-flameproof type resin may further comprise aUL94-HB material. The substrate may further comprise Duroid, Benzocyclobutane, Roger 4350, FR4-epoxy, Bakelite.

As illustrated, in some examples, the conductive layer 40 may be affixedto the substrate 50 using first adhesive sheet 52, which may bepositioned between the conductive layer 40 and the substrate 50. In someexamples, the antenna 21, 31 may include a second adhesive sheet 54,utilized for laminating the rear connection terminals 47, 48 to theunderside of the substrate 50. The rear connection terminals 47, 48 maybe connected to one or more connectors of the conductive layer 40 via,for example, a spot welding process performed during manufacture of theantenna 21, 31. In order to allow both conductive layers to be spotwelded, there may be cutouts or splits in the adhesive sheets on one orboth sides.

Turning now to FIG. 6 and with continued reference to FIGS. 5A-C, ablock diagram for a method 100 for manufacturing an antenna 21A, 31A isillustrated. The method 100 begins at block 102, wherein theprefabricated PCB 70 is more or more of provided, designed, and/ormanufactured, prior to the formation of the antenna 21, 31 via themethod 100. The prefabricated PCB 70 includes an unetched coil area 60,for use in fabricating the antenna 21, 31.

Accordingly, at block 110, a first sheet of a conductive metal for thecoil area 60 is provided. The conductive metal may be a metal from whichone or more of the PCB design 72, the traces 74, the vias 76, the coilarea 60, or combinations thereof are formed. The conductive metal may beany conductive metal, such as, but not limited to, copper and/or copperalloys, aluminum and aluminum alloys, iron and iron alloys, nickel andnickel alloys, silver and/or silver alloys, and gold and/or gold alloys.The conductive metal of an antenna may further be selected from thegroup consisting of copper, aluminum, silver, nickel, gold, stainlesssteel, phosphorus bronze, beryllium-copper alloys, copper-nickel,nickel-chromium, conductive polymer thick film composites,toner/lithographic inks, and combinations thereof. In some examples,wherein the conductive metal is copper and/or a copper alloy, the copperand/or copper alloy may be one or more of half-ounce copper, one-ouncecopper, two-ounce copper, or any combinations thereof. The first sheetis a conductive metal that is suitable for use in forming one or more ofthe layer 40, the coil turns 42, the connection terminals 45, 46, 47,48, or any combinations thereof.

The method 100 further includes providing one or more of the firstadhesive sheet 52 and the second adhesive sheet 54, as illustrated inblock 120. The first and second adhesive sheets 52, 54 may be pressuresensitive adhesives (PSA), configured for affixing the first sheet forthe conductive layer 40 to the substrate 50, as illustrated at block125. Such PSAs, for use as one or both of the adhesive sheets 52, 54,may comprise or include one or more of an acrylic, a rubber, a tape, aglue, or any combinations thereof. PSAs may be particularly useful, asthey may not solidify to form a solid material, but remain viscous. As aresult, PSAs remain permanently tacky and have the ability to wetsurfaces on contact. Bonds are made by bringing the PSA in contact withthe substrate and applying pressure. A PSA sheet may comprise backing,the backing comprising one of a cloth, a paper, a metal, a plastic orcombinations thereof. The backing may be coated on one (single coated)or both (double coated) sides by the permanently tacky adhesive. Thepermanently tacky adhesive is adherable to a variety of surfaces withlight pressure (finger pressure) and with no phase change (liquid tosolid). A PSA may be provided as a single sheet fit to size or in a rollform so that the sheet can be cut to a specific size in accordance withthe need of an application. PSAs can be blends of natural or syntheticrubber and resin, acrylic, silicone or other polymer systems, with orwithout additives. Pending the design of an antenna, the antenna maycomprise a single coated PSA sheet, a double coated PSA sheet, orcombinations thereof. PSAs are typically formulated from natural rubber,certain synthetic rubbers, and polyacrylates.

Additionally or alternatively, the adhesive sheets 52, 54 may includeone or more of high-performance flex and rigid-flex laminates andadhesive systems. Such flex and rigid-flex laminates and adhesivesprovide for flexible laminates, embedded passives and thermalperformance for demanding applications, and may also include coredielectric materials and customized constructions that enable low losshigh-speed high-frequency applications, high service temperatureapplications and allow options for single sided and double-sided,multi-layer flex and rigid -flex antenna designs. The adhesive sheets52, 54 may be acrylic-based, polyimide-based, epoxy-based, modifiedepoxy-based, fluoropolymer-based, polyester-based, phenolic-based, andinclude copper-clad type adhesive sheets. In some examples, the adhesivesheets 52, 54 may include a tape, such as a Tesa tape, which may bechosen based on a specific application and can be selected for one ormore of low cost, high operating temperature, environmentalcharacteristics, among other things.

With the first layer for the conductive layer 40 affixed to thesubstrate 50, the method 100 then includes applying an etch resistantcoating (ERC) on, at least, a coil area 60 of the first sheet for theconductive layer 40, as illustrated in block 130. As illustrated withdotted lines in FIG. 5A, the coil area 60 may be any area on thepre-etched/laser cut first layer for the conductive layer, on which theresultant conductive layer 40 sill reside, including all of the turns42, connection terminals 45, 46, gaps 44, among other conductive layer40 characteristics. The etch resistant coating is utilized to keepportions of the first sheet, from which the first conductive layer 40will be formed, from disintegrating off of the substrate 50, when thesubstrate 50, with the first sheet affixed, is exposed to an etchingsolution. The etch resistant coating is a compound capable to resistetching by common chemicals used in PCB manufacturing process, such a,but not limited to, cupric chloride (CuCl2) or Ferric chloride (FeCl3).The etch resistant coating may be easy to remove (e.g., washable) orpermanent. While etch resists commonly used in PCB etching may requirean exposure to activate resistant characteristics prior to etching, itis important to note that the ERC does not require a light or any otherelectro-magnetic radiation source of exposure, or any alternative sourceof exposure, for it to be resistive to an etching solution. The etchresistant coating may be any proper etch resistant coating known in theart, such as, but not limited to, a lamination, a polymer compound thatis applied via spraying or as a thin film from a roll, a metal basedthin film created by way of electrochemical plating or vapor depositionin a vacuum (PVD), or combinations thereof. ERC can be sub-micron thin(PVD), or as thick as 50 micrometers (e.g., a spray coating or film).

In some examples, the method 100 includes determining one or both of thecoil area 60 and a laser cutting path for the first conductive layer 40,as illustrated in block 140. Determining the coil area 60 may includedetermining one or more of a geometry 62 for the conductive layer 40, alocation relative to the substrate 50 for the first conductive layer 40and/or components thereof, locations for turns 42 and/or gaps 44 of theconductive layer 40, or combinations thereof. Determining the lasercutting path for the conductive layer 40 may include determining a pathfor a laser to cut features of the conductive layer into the firstsheet. Laser cutting will be discussed in more detail below, withreference to block 150. The laser cutting path may include instructionsfor generating the coil geometry 62, which may include geometry for oneor more of the turns 42, the gaps 44, the connection terminals 45, 46,47, 48, any other geometric features of the conductive layer 40, orcombinations thereof. The laser cutting path may be a simulation,program, and/or electronic document to be utilized by a controllerassociated with a laser, for cutting the coil geometry 62 into the firstsheet, to form the conductive layer 40. Alternatively, the laser cuttingpath may be instructions provided to a user of a laser, the user guidingthe laser, based on the laser cutting path, for cutting the coilgeometry 62 into the first sheet, to form the conductive layer 40.

At block 150, the method 100 includes laser cutting the first sheet, atleast within the coil area 60, based on the laser cutting path of block140. The coil geometry 62 includes, at least, instructions defining aplurality of turns for the first conductive layer 40 for the antenna21A, 31A. The first geometry 62 may be configured to generate a coil forthe antenna 21A, 31A, at the first layer 40, such that the antenna 21A,31A is utilized for one or more of transmission of wireless powersignals, receipt of wireless power signals, and combinations thereof.The laser used for block 150 may be any suitable cutting laser, suchthat the laser is capable of cutting through, at least in part, theconductive metal layer of the first sheet for the conductive layer 40.

Laser cutting may comprise either a pulsed beam or a continuous wavebeam, with the former being delivered in short bursts while the latterbeing delivered continuously. Laser beam intensity, length and heatoutput may be controlled depending on the material being laser cut. Amirror or special lens can further be used to fine-focus the laser beamfor precision coil-to-coil spacing, demanding coil turn structures,critical gap dimensions and/or demanding tolerance requirements forsame. The laser for block 150 may include one or more of a gas laser, acrystal laser, a fiber laser, and/or other lasers, which are capable ofcutting through, at least in part, a conductive metal. A gas laser forblock 150 may further comprise a CO2 laser, the crystal laser mayfurther comprise an nd:YAG (neodymium-doped yttrium aluminum garnet)laser or an nd:YVO (neodymium-doped yttrium ortho-vanadate) laser, andthe fiber laser may further comprise a glass fiber laser, comprising asolid gain medium and a ‘seed laser’, wherein the ‘seed laser’ producesa laser beam that is then amplified using glass fibers and pump diodes.

After the laser cutting of block 150 is performed, the method 100includes exposing the first sheet in an etching solution, to removeunwanted conductive metal from the first sheet and/or the substrate 50,upon which the first sheet for the conductive layer 40 lies.Accordingly, submerging the first sheet in the etching solution mayremove substantially all of the conductive materials of the first sheet,outside of the coil area 60. Locations within the coil area 60, uponwhich the etch resistant coating of block 130 was applied and not cut bythe laser, should substantially remain affixed to the substrate 50 andbe utilized to form the conductive layer 40. The solution(s),chemical(s), apparatus, and/or process(es) of the etching solution forblock 150 may include, but are not limited to including, one or more ofacids, alkalies, alcohols, halogens, and combinations thereof in whichthe material to be etched is soluble. The solution(s), chemical(s),apparatus, and/or process(es) of the etching solution for block 150 mayinclude, but are not limited to including, mixed acids, ionic gases,molten fluxes, and combinations thereof. For example, copper and copperalloys are soluble in HNO₃, hot H₂S0₄, HCl and NH₄OH. FeCl₃, mixedacids, ionized gases and combinations thereof. Etchants for copper andcopper alloys therefore may comprise an alkali etch such as NaOH, H₂S0₄and HNO₃, or an acid etch selected such as a concentrated HNO₃, or adilute HNO₃, or a dilute HCl, or HNO₃ and FeCl₃. The etchants for copperare not meant to be limiting, but only exemplary to the invention. It isunderstood that the chemical etchant is selected in accordance with thesolubility of the material being etched. One is referred to the Handbookof Metal Etchants, ISBN 0-8493-3623-6, the contents of which are fullyincorporated herein by this reference, for guidance in the selection ofchemical etchants

By performing the laser cutting of block 150 prior to exposing the firstsheet in the etching solution at block 160, the laser cutting of thecoil geometry 62, will remove the substantially all of the etchresistant coating and at least some of the conductive metal, fromlocations on the conductive metal, such locations defining, at least,the turn gaps 44 of the antenna 21, 31. Accordingly, while the lasercutting of block 150 may remove all conductive metals of the first sheetat the locations for the turn gaps 44, in some examples the lasercutting may not remove all materials within the area of the coil area 60designated for the gaps 44, in accordance with the coil geometry 62.Therefore, the process of block 160, as performed after the process of150, may remove excess materials from within the intended gaps 44 of thecoil geometry 62; thus avoiding shorts between turns 44 due to impropergaps and/or etching more precise gaps, in comparison to a laser cuttingand/or etching, performed alone.

By utilizing blocks 150 and 160, in succession, smaller gaps betweenneighboring traces 44 are achieved, compared to legacy processes foretching PCB wireless power antennas. Because the excess materials thatmay be left in the gaps 44 can be removed, as the laser cutting hasremoved the etch resistant coating from the locations of the gaps 44 inthe coil area, the etching process of block 160 will effectively removeany unwanted conductive metal still residing within the intended gaps44. Thus, this combination of steps in the method 100 allows for smallercuts to be made, via lasers, with the additional step of clearance ofsaid gaps by etching; said smaller cuts will generate smaller gaps 44and larger traces 42, within a given coil area 60. An antenna 21A, 31Awith wider traces 42 and/or smaller gaps 44 and/or a greater number ofturns 42 allowed within the coil area 60 may result in an antenna 21A,31A with greater performance characteristics, in comparison to a similarantenna with a coil area similar to the coil area 60, but havingnarrower traces and/or larger gaps and/or less turns within itsrespective coil area. More specifically, antennas 21A, 31A, asmanufactured with the method 100, may have a greater quality factorand/or prove more efficient for wireless power receipt when used as areceiver antenna 31 of the receiver system 30. Further, such antennas 31manufactured according to the method 100 may be particularly useful inlower frequency wireless power receipt applications, such as, but notlimited to, use in Qi wireless power receivers, operating at anoperating frequency in a range of about 87 kHz to about 205 kHz.

Returning now to the method 100, after etching at block 160, the method100 may include removing the first sheet from the etching solution, asillustrated at block 170. After removing the first sheet from theetching solution, the method may further include providing and affixinga coverlay to one or more of a front of the substrate and/or conductivelayer 40 and a rear of the substrate and/or any conductive layersthereon, as illustrated in block 180. The coverlay may be any coveringintended to insulate, protect, and/or otherwise obscure a face of theantenna 21A, 31A, such as, but not limited to, a laminating of theantenna 21A, 31A.

Turning now to FIGS. 7A-C, another embodiment of an antenna 21B, 31B ona prefabricated PCB 70B is illustrated. The prefabricated PCB 70B and/orthe antenna 21B, 31B may include similar and/or equivalent elements tothose of the prefabricated PCB 70A and/or the antenna 21A, 31A of FIGS.5 and, thus, the descriptions of elements of FIGS. 5 may be utilized indescribing like elements of FIGS. 7 . While not shown, the prefabricatedPCB 70B may include a PCB design 72B, for one or more layers of theprefabricated PCB 70B, the PCB design 72B including like or similarelements to the PCB design 72A of FIGS. 5 .

In contrast to the antenna and PCB of FIGS. 5 , the antenna 21B, 31Bincludes multiple conductive antenna layers 40, such as, but not limitedto, a first conductive layer 40B and a second conductive later 40C. Thefirst conductive layer 40B may be affixed to a first side 55 of asubstrate 50B and the second layer may be affixed to a second side 56 ofthe substrate 50B. The first conductive layer 40B may be formed inaccordance with a coil geometry 62B at a coil area 60B, wherein the coilgeometry 62B provides guidance for forming first traces 42B with firstgaps 44B therebetween. Similarly, the second conductive layer 40C may beformed in accordance with a coil geometry 62C at a coil area 60C,wherein the coil geometry 62C provides guidance for forming secondtraces 42C with second gaps 44C therebetween. Additionally, the firstconductive layer 40B includes first and second connection terminals 45B,46B and the second conductive layer 40C includes third and fourthconnection terminals 47C, 48C. In some examples, the first and secondterminals 45B, 46B may be connected in electrical parallel with thethird and fourth connection terminals 47C, 48C, with respect to anincoming current to the antenna 21B, 31B. Further, similar to theadhesive layer 52 of FIGS. 5 , as best illustrated in FIG. 7C, theantenna 21B, 31B may include first and second adhesive layers 52, 54utilized for affixing the first and second conductive layers 40B, 40C tothe first and second sides 55, 56 of the substrate 50B.

Additionally, the antenna 21B, 31B may be formed in accordance withblocks similar to those of the method 100 of FIG. 6 , with multipleblocks repeated for each of the conductive layers 40. To that end, FIG.8 is a block diagram for a method 200 for manufacturing the antenna 21B,31B. The method 200 includes similar and/or equivalent blocks to thoseof the method 100 of FIG. 6 and, thus, similar and/or analogous numberlabelling is used and the descriptions, with respect to FIG.6, of saidblocks apply to those similar elements of FIG. 8 .

The method 200 begins at block 102, wherein the prefabricated PCB 70 ismore or more of provided, designed, and/or manufactured, prior to theformation of the antenna 21, 31 via the method 200. The prefabricatedPCB 70 includes an unetched coil area 60, for use in fabricating theantenna 21, 31, on one or more layers of the prefabricated PCB 70. Themethod 200 continues with one or more of providing first and secondsheets for the conductive layers 40B, 40C (blocks 110B, 110C), providingthe adhesive layers 52B, 54C (blocks 120B, 120C), and affixing the firstand second sheets for the conductive layers 40B, 40C to the substrate50B using the adhesive layers 52B, 54C (blocks 125B, 125C). The firstsheet for the first conductive layer 40B may be affixed to the firstside 55 of the substrate 50B and the second sheet for the secondconductive layer 40C may be affixed to the second side 56 of thesubstrate 50B.

At block 210, the method 200 includes spot welding the first sheet forthe first conductive layer 40B to the second sheet for the secondconductive layer 40C. Such spot welding may be performed through thesubstrate 50B at, for example, one or more of a through hole, a via,forming an opening in the substrate, or any combinations thereof,amongst other connectors for the first and second conductive layers 40C.In some examples, the spot welding of block 210 may connect the firstand second conductive layers 40B, 40C at a spot in the respective coilareas 60B, 60C that are designated by the coil geometries 60B, 60C forconnection terminals 45B, 46B, 47C, 48C. For example, the spot weldingmay be configured such that, after laser cutting and etching, said weldswill connect the first connection terminal 45B with the third connectionterminal 47C and connect the second terminal 46B with the fourthconnection terminal 48C, such that the first conductive layer 40B andthe second conductive layer 40C are in electrical parallel, with respectto an electrical current entering/exiting the conductive layers 40B, 40Cat the connection terminals 45B, 46B, 47C, 48C.

After step 210, the method 200 may include blocks 100B and 100C, whereinone or more blocks/steps of the method 100 may be repeated for each ofthe first sheet and second sheet, to form the first and secondconductive layers 40B, 40C and all features thereof. Accordingly, block100B may include performing blocks 140, 150, 160, 170, and/or 180 of themethod 100, to the first sheet for the first conductive layer 40B.Similarly, block 100C may include performing blocks 140, 150, 160, 170,and/or 180 of the method 100, to the second sheet for the secondconductive layer 40C.

As discussed above, performing the methods 100, 200 in manufacturing oneor more of the antennas 21A, 31A, 21B, 31B may allow for the ability tomanufacture higher efficiency and/or quality factor (Q) antennas forwireless power transfer, due to one or more of decrease in gap width,increases in turn width, or increases in number of turns within a givenarea. Experimental results have shown that, when using the systems andmethods disclosed herein, beneficial, narrow gap widths, which result inthe benefits discussed above, are achieved at various thicknesses ofcopper for the metal sheets, such as a gap of about 50 microns when thecopper is about half-ounce copper, a gap of about 75 microns when thecopper is about one-ounce copper, a gap of about 100 microns when thecopper is two-ounce copper, and a gap of about 125 microns when thecopper is three-ounce copper. Further, even smaller gaps can beachieved, utilizing laser technology with further advanced precisionand/or power of operations. Such narrow gap widths may allow for theperformance benefits and/or electrical characteristics, discussed above.

In some example experimental results wherein two ounce copper was usedfor the sheets of metal that were cut and etched to form the conductivelayer(s) 40, utilizing the systems and methods disclosed herein, it wasfound that the processes could consistently achieve gap widths of about90-100 microns between turns of the conductive layer(s). Power transfercharacteristic test measurements were performed on the experimental testresults of the systems and methods disclosed herein and antennas 21, 31,with envelope dimensions measuring 45×45 mm, were produced having atleast about a 10 percent to 15 percent improvement in one or both ofquality factor (Q) or equivalent series resistance (ESR) in the antenna21, 31, when compared to a comparable antenna, manufactured via known,conventional means for producing a PCB antenna of the same or similartopology. Further, it was found that improvements in efficiency, Q, andESR were more pronounced in antennas configured for operation at loweroperating frequencies, such as those in a range of about 87 kHz to about205 kHz.

Images illustrating experimental results utilizing the systems andmethods of FIGS. 5-8 are illustrated in FIGS. 9 and 10 . FIG. 9 shows azoomed in image of a conductive layer for a cut 247 made by a laser usedin performing functions of the systems and methods of FIGS. 5-8 . Asillustrated, the cut 247 may not fully penetrate the conductive metallayer and, thus, may cause a short in an antenna made from theconductive material. Accordingly, as discussed above, an etching processmay then be used to clear out the cut 247 in the conductive layer toproduce a suitable trace gap for an antenna.

FIG. 10 illustrates such a scenario, wherein a laser cut (e.g., the cut247 of FIG. 9 ) is made and then the conductive layer, upon which one ormore of such cuts lie, is submerged in an etching solution, as discussedabove with reference to FIGS. 5-8 . FIG. 10 shows a trace gap 247produced by the systems and methods of FIGS. 5-8 . By utilizing thesystems and methods of 5-8, the trace gap 247 extends from the topsurface of the conductive metal all the way to the top surface of asubstrate, upon which the conductive layer lies; thus, by utilizing thesystems and methods of FIGS. 5-8 , the trace gap 247 is produced withoutcausing any shorts in the resultant antenna of the conductive metal.

Additionally, due to the utilization of the systems and methods of FIGS.5-8 , the trace gap 247 may be considerably narrower than the narrowesttrace gaps that can be produced by a traditional PCB etching process forproducing an antenna. For example, FIG. 11 illustrates a trace gap 344on a comparable conductive metal sheet for a similarly typed antenna asthose of the image of FIG. 10 . The images of FIGS. 10 and 11 areproduced at a relatively comparable size scale and, as shown, such scaleelucidates that a width of the trace gap 247, produced by the systemsand methods of FIGS. 5-8 , may be significantly narrower than a width ofthe trace gap 344, produced by traditional PCB etching processes. Forexample, the trace gap 247 may have a width in a range of about 0.05millimeters (mm) to about 0.095 mm, whereas the trace gap 347 may have awidth in a range of about 0.125 mm to about 0.2 mm. As discussed above,smaller trace gaps produce significant benefits on performance of suchantennas and, thus, utilizing the systems and methods disclosed hereinprovides for improved antennas versus antennas produced by legacy PCBetching methods, as exemplified by the comparison of FIGS. 10 and 11 .

In addition to performance benefits achieved via the systems and methodsdisclosed herein, the utilization of the combination of laser cuttingand chemical etching results in a decrease in time spent manufacturingthe antennas 21, 31, in comparison to manufacturing legacy antennas.Additionally, the systems and methods disclosed herein can provide forboth faster and more cost-effective manufacturing, by utilizing thelaser cutting and chemical etching combination, to accelerate the speedof production of said antennas 21, 31.

As used herein, the phrase “at least one of” preceding a series ofitems, with the term “and” or “or” to separate any of the items,modifies the list as a whole, rather than each member of the list (i.e.,each item). The phrase “at least one of” does not require selection ofat least one of each item listed; rather, the phrase allows a meaningthat includes at least one of any one of the items, and/or at least oneof any combination of the items, and/or at least one of each of theitems. By way of example, the phrases “at least one of A, B, and C” or“at least one of A, B, or C” each refer to only A, only B, or only C;any combination of A, B, and C; and/or at least one of each of A, B, andC.

The predicate words “configured to”, “operable to”, and “programmed to”do not imply any particular tangible or intangible modification of asubject, but, rather, are intended to be used interchangeably. In one ormore embodiments, a processor configured to monitor and control anoperation or a component may also mean the processor being programmed tomonitor and control the operation or the processor being operable tomonitor and control the operation. Likewise, a processor configured toexecute code can be construed as a processor programmed to execute codeor operable to execute code.

A phrase such as “an aspect” does not imply that such aspect isessential to the subject technology or that such aspect applies to allconfigurations of the subject technology. A disclosure relating to anaspect may apply to all configurations, or one or more configurations.An aspect may provide one or more examples of the disclosure. A phrasesuch as an “aspect” may refer to one or more aspects and vice versa. Aphrase such as an “embodiment” does not imply that such embodiment isessential to the subject technology or that such embodiment applies toall configurations of the subject technology. A disclosure relating toan embodiment may apply to all embodiments, or one or more embodiments.An embodiment may provide one or more examples of the disclosure. Aphrase such an “embodiment” may refer to one or more embodiments andvice versa. A phrase such as a “configuration” does not imply that suchconfiguration is essential to the subject technology or that suchconfiguration applies to all configurations of the subject technology. Adisclosure relating to a configuration may apply to all configurations,or one or more configurations. A configuration may provide one or moreexamples of the disclosure. A phrase such as a “configuration” may referto one or more configurations and vice versa.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any embodiment described herein as“exemplary” or as an “example” is not necessarily to be construed aspreferred or advantageous over other embodiments. Furthermore, to theextent that the term “include,” “have,” or the like is used in thedescription or the claims, such term is intended to be inclusive in amanner similar to the term “comprise” as “comprise” is interpreted whenemployed as a transitional word in a claim. Furthermore, to the extentthat the term “include,” “have,” or the like is used in the descriptionor the claims, such term is intended to be inclusive in a manner similarto the term “comprise” as “comprise” is interpreted when employed as atransitional word in a claim.

All structural and functional equivalents to the elements of the variousaspects described throughout this disclosure that are known or latercome to be known to those of ordinary skill in the art are expresslyincorporated herein by reference and are intended to be encompassed bythe claims. Moreover, nothing disclosed herein is intended to bededicated to the public regardless of whether such disclosure isexplicitly recited in the claims. No claim element is to be construedunder the provisions of 35 U.S.C. § 112, sixth paragraph, unless theelement is expressly recited using the phrase “means for” or, in thecase of a method claim, the element is recited using the phrase “blockfor.”

Reference to an element in the singular is not intended to mean “one andonly one” unless specifically so stated, but rather “one or more.”Unless specifically stated otherwise, the term “some” refers to one ormore. Pronouns in the masculine (e.g., his) include the feminine andneuter gender (e.g., her and its) and vice versa. Headings andsubheadings, if any, are used for convenience only and do not limit thesubject disclosure.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of what may be claimed, but ratheras descriptions of particular implementations of the subject matter.Certain features that are described in this specification in the contextof separate embodiments can also be implemented in combination in asingle embodiment. Conversely, various features that are described inthe context of a single embodiment can also be implemented in multipleembodiments separately or in any suitable sub-combination. Moreover,although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to a subcombination or variation of a sub combination.

1. A method for manufacturing a printed circuit board (PCB) for awireless power transfer system, the PCB including an antenna, theantenna including a coil configured to operate at an operating frequencyselected from a range of about 87 kilohertz (kHz) to about 205 kHz, themethod comprising: providing a prefabricated PCB, the prefabricated PCBincluding a PCB design and a first area; providing a first sheet of aconductive metal, the first sheet including the first area; applying anetch resistant coating on a coil area within the first area; lasercutting the first sheet within the coil area, based on a laser cuttingpath, the laser cutting path defining a first geometry for a firstplurality of turns for a first layer of the coil, the first geometryconfigured for one or more of transmission of wireless power signals,receipt of wireless power signals, and combinations thereof; andsubstantially exposing the first sheet to an etching solution, theetching solution substantially removing first portions of the conductivemetal from a substrate to define, at least, first turn gaps between atleast two of the first plurality of turns.
 2. The method of claim 1,further comprising determining the coil area based, at least, on anexterior geometry for the first layer of the coil.
 3. The method ofclaim 1, further comprising determining the laser cutting path based, atleast, on one or more of the first geometry, a number of turns for thefirst plurality of turns, and any combinations thereof.
 4. The method ofclaim 1, wherein the PCB design includes one or more of at least onetrace, at least one via, or combinations thereof.
 5. The method of claim4, further comprising providing a pressure sensitive adhesive in betweenthe first sheet and the substrate, and wherein affixing the first sheetto the substrate includes affixing the first sheet to the substrate viathe pressure sensitive adhesive.
 6. The method of claim 4, furthercomprising providing a coverlay substantially covering the first layerof the coil and the substrate.
 7. The method of claim 1, furthercomprising: providing a second sheet of a conductive metal, the secondsheet defining a second area; applying an etch resistant coating on asecond coil area within the second area; laser cutting the second sheetwithin the second coil area, based on a second laser cutting path, thesecond laser cutting path defining a second geometry for a secondplurality of turns for a second layer of the coil, the second geometryconfigured for one or more of transmission of wireless power signals,receipt of wireless power signals, and combinations thereof; andsubstantially exposing the second sheet to an etching solution, theetching solution substantially removing second portions of theconductive metal, the second portions positioned to define, at least,turn gaps between at least two of the second plurality of turns.
 8. Themethod of claim 1, wherein the conductive metal is copper.
 9. The methodof claim 8, wherein the conductive metal is half-ounce copper, andwherein the first geometry defines at least one gap between two of thefirst plurality of turns is less than about 50 microns.
 10. The methodof claim 8, wherein the conductive metal is one-ounce copper and whereinthe first geometry defines at least one gap between two of the firstplurality of turns is less than about 75 microns.
 11. The method ofclaim 8, wherein the conductive metal is two-ounce copper and whereinthe first geometry defines at least one gap between two of the firstplurality of turns is less than about 100 microns.
 12. The method ofclaim 8, wherein the conductive metal is three-ounce copper and whereinthe first geometry defines at least one gap between two of the firstplurality of turns is less than about 125 microns.
 13. A method formanufacturing a printed circuit board (PCB) for a wireless powertransfer system, the PCB including an antenna, the antenna including amulti-layered coil having, at least, a first layer and a second layer,the multi-layered coil configured to operate at an operating frequencyselected from a range of about 87 kilohertz (kHz) to about 205 kHz, themethod comprising: providing a prefabricated PCB, the prefabricated PCBincluding a PCB design, a first area, and a second area; providing afirst sheet of a conductive metal, the first sheet including the firstarea; providing a second sheet of the conductive metal, the second sheetdefining the second area; applying an etch resistant coating on a firstcoil area within the first area; applying an etch resistant coating on asecond coil area within the second area; laser cutting the first sheetwithin the first coil area, based on a first laser cutting path, thefirst laser cutting path defining a first geometry for a first pluralityof turns for a first layer of the multi-layered_coil, the first geometryconfigured for one or more of transmission of wireless power signals,receipt of wireless power signals, and combinations thereof; lasercutting the second sheet within the second coil area, based on a secondlaser cutting path, the second laser cutting path defining a secondgeometry for a second plurality of turns for a second layer of themulti-layered coil, the second geometry configured for one or more oftransmission of wireless power signals, receipt of wireless powersignals, and combinations thereof; substantially exposing the firstsheet to an etching solution, the etching solution substantiallyremoving first portions of the conductive metal from a substrate todefine, at least, first turn gaps between at least two of the firstplurality of turns; and substantially exposing the second sheet to anetching solution, the etching solution substantially removing secondportions of the conductive metal from the substrate to define, at least,second turn gaps between at least two of the second plurality of turns.14. The method of claim 13, further comprising welding the first layerof the multi-layered coil to the second layer of the multi-layered coil.15. The method of claim 14, wherein welding the first layer of themulti-layered coil to the second layer of the multi-layered coilincludes spot welding the first layer of the multi-layered coil to thesecond layer of the multi-layered coil at a via.
 16. The method of claim15, wherein the via is configured to connect the first layer of themulti-layered coil to the second layer of the multi-layered coil in aparallel electrical connection.
 17. The method of claim 13, furthercomprising: affixing the first sheet to a top face of the substrate; andaffixing the second sheet to a bottom face of the substrate.
 18. Themethod of claim 17, further comprising: providing a first pressuresensitive adhesive in between the first layer and the top face of thesubstrate; and providing a second pressure sensitive adhesive in betweenthe second layer and the bottom face of the substrate, wherein affixingthe first sheet to the top face of the substrate includes affixing thefirst sheet to the top face of the substrate via the first pressuresensitive adhesive, and wherein affixing the second sheet to the bottomface of the substrate includes affixing the second sheet to the bottomface of the substrate via the second pressure sensitive adhesive.
 19. Anantenna for a wireless power transfer system, the antenna configured tooperate at an operating frequency selected from a range of about 87kilohertz (kHz) to about 205 kHz, the antenna comprising: a coil, thecoil including a first layer, the first layer defining a first pluralityof turns, the first plurality of turns formed by: providing aprefabricated printed circuit board (PCB), the prefabricated PCBincluding a PCB design and a first area, providing a first sheet of aconductive metal, the first sheet including a first area, applying anetch resistant coating on a coil area within the first area, lasercutting the first sheet within the coil area, based on a laser cuttingpath, the laser cutting path defining a first geometry for the firstplurality of turns for the first layer of the coil, the first geometryconfigured for one or more of transmission of wireless power signals,receipt of wireless power signals, and combinations thereof, andsubstantially exposing the first sheet to an etching solution, theetching solution substantially removing first portions of the conductivemetal from a substrate to define, at least, first turn gaps between atleast two of the first plurality of turns.
 20. The antenna of claim 19,wherein the coil further includes a second layer, the second layerdefining a second plurality of turns, the second plurality of turnsformed by: providing a second sheet of a conductive metal, the secondsheet defining a second area, applying an etch resistant coating on asecond coil area within the second area, laser cutting the second sheetwithin the second coil area, based on a laser cutting path, the lasercutting path defining a second geometry for the second plurality ofturns for the second layer of the coil, the second geometry configuredfor one or more of transmission of wireless power signals, receipt ofwireless power signals, and combinations thereof, substantially exposingthe second sheet to an etching solution, the etching solutionsubstantially removing second portions of the conductive metal from thesubstrate to define, at least, second turn gaps between at least two ofthe second plurality of turns, wherein the first layer is affixed to atop face of the substrate, and wherein the second layer is affixed to abottom face of the substrate.